Add test to draw multisample polygons with GL_POLYGON_SMOOTH enabled

This test varifies that GL_POLYGON_SMOOTH is ignored in case of multisample
polygons.

Note: This test passes on AMD's catalyst and NVIDIA drivers.

V2: Polygon smoothing is applied uniformly to all attached buffers. So, It is
    redundant to test on depth and stencil buffers. Made the changes to remove
    the redundant code.

Signed-off-by: Anuj Phogat <anuj.phogat@gmail.com>
Reviewed-by: Paul Berry <stereotype441@gmail.com>

3 files changed, 168 insertions, 0 deletions

diff --git a/tests/all.tests b/tests/all.tests
index 15e1549d1..93716a86d 100644
--- a/tests/all.tests
+++ b/tests/all.tests
@@ -1367,6 +1367,12 @@ for num_samples in (2, 4, 8, 16, 32):
 	        test_name)
 	ext_framebuffer_multisample[test_name] = PlainExecTest(executable)
 
+for num_samples in (2, 4, 8, 16, 32):
+	test_name = ' ' .join(['polygon-smooth', str(num_samples)])
+	executable = 'ext_framebuffer_multisample-{0} -auto'.format(
+	        test_name)
+	ext_framebuffer_multisample[test_name] = PlainExecTest(executable)
+
 ext_framebuffer_object = Group()
 spec['EXT_framebuffer_object'] = ext_framebuffer_object
 add_fbo_stencil_tests(ext_framebuffer_object, 'GL_STENCIL_INDEX1')
diff --git a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
index 5780e24a1..155190fee 100644
--- a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
+++ b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
@@ -20,6 +20,7 @@ piglit_add_executable (ext_framebuffer_multisample-negative-max-samples negative
 piglit_add_executable (ext_framebuffer_multisample-negative-mismatched-samples negative-mismatched-samples.c)
 piglit_add_executable (ext_framebuffer_multisample-negative-readpixels negative-readpixels.c)
 piglit_add_executable (ext_framebuffer_multisample-point-smooth common.cpp point-smooth.cpp)
+piglit_add_executable (ext_framebuffer_multisample-polygon-smooth common.cpp polygon-smooth.cpp)
 piglit_add_executable (ext_framebuffer_multisample-renderbuffer-samples renderbuffer-samples.c)
 piglit_add_executable (ext_framebuffer_multisample-renderbufferstorage-samples renderbufferstorage-samples.c)
 piglit_add_executable (ext_framebuffer_multisample-samples samples.c)
diff --git a/tests/spec/ext_framebuffer_multisample/polygon-smooth.cpp b/tests/spec/ext_framebuffer_multisample/polygon-smooth.cpp
new file mode 100644
index 000000000..dc086a4ca
--- /dev/null
+++ b/tests/spec/ext_framebuffer_multisample/polygon-smooth.cpp
@@ -0,0 +1,161 @@
+/*
+ * Copyright © 2012 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "common.h"
+
+/**
+ * \file polygon-smooth.cpp
+ *
+ * Page 134 (in the PDF) of the OpenGL 3.0 spec says:
+ * "If MULTISAMPLE is enabled, and the value of SAMPLE BUFFERS is one,
+ * then polygons are rasterized using the following algorithm, regardless
+ * of whether polygon antialias-ing (POLYGON_SMOOTH) is enabled or disabled".
+ *
+ * This test operates by drawing a test pattern in to multisample fbo with
+ * GL_POLYGON_SMOOTH disabled. Blits it in to right half of window system
+ * framebuffer. This is used as reference image.
+ *
+ * Draw the same test pattern for the second time in multisample buffer with
+ * GL_POLYGON_SMOOTH enabled. Blit it in to left half of window system
+ * framebuffer. This is the test image.
+ *
+ * To verify that GL_POLYGON_SMOOTH is ignored during MSAA, compare the two
+ * halves of default framebuffer. They are expected to match.
+ */
+
+int piglit_width = 512; int piglit_height = 256;
+int piglit_window_mode =
+	GLUT_DOUBLE | GLUT_RGBA | GLUT_ALPHA | GLUT_DEPTH | GLUT_STENCIL;
+const int pattern_width = 256; const int pattern_height = 256;
+
+Fbo ms_fbo;
+Test *test = NULL;
+GLbitfield buffer_to_test;
+TestPattern *test_pattern = NULL;
+
+void
+print_usage_and_exit(char *prog_name)
+{
+	printf("Usage: %s <num_samples>\n",
+	       prog_name);
+	piglit_report_result(PIGLIT_FAIL);
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	int num_samples;
+	if (argc < 2)
+		print_usage_and_exit(argv[0]);
+	{
+		char *endptr = NULL;
+		num_samples = strtol(argv[1], &endptr, 0);
+		if (endptr != argv[1] + strlen(argv[1]))
+			print_usage_and_exit(argv[0]);
+	}
+
+	piglit_require_gl_version(30);
+
+	/* Skip the test if num_samples > GL_MAX_SAMPLES */
+	GLint max_samples;
+	glGetIntegerv(GL_MAX_SAMPLES, &max_samples);
+	if (num_samples > max_samples)
+		piglit_report_result(PIGLIT_SKIP);
+
+	buffer_to_test = GL_COLOR_BUFFER_BIT;
+
+	test_pattern = new Triangles();
+	test_pattern->compile();
+
+	ms_fbo.init(num_samples, pattern_width, pattern_height,
+		     true /* combine_depth_stencil */,
+		     false /* attach_texture */);
+
+	/* Enable blending to test GL_POLYGON_SMOOTH */
+	glEnable (GL_BLEND);
+	glBlendFunc (GL_SRC_ALPHA_SATURATE, GL_ONE);
+}
+
+enum piglit_result
+piglit_display()
+{
+	bool pass = true;
+	float proj[4][4] = {
+		{ 1, 0, 0, 0 },
+		{ 0, 1, 0, 0 },
+		{ 0, 0, 1, 0 },
+		{ 0, 0, 0, 1 }
+	};
+
+	/* Draw test pattern in  multisample ms_fbo with GL_POLYGON_SMOOTH
+	 * disabled.
+	 */
+	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, ms_fbo.handle);
+	ms_fbo.set_viewport();
+	test_pattern->draw(proj);
+
+	/* Blit ms_fbo to the right half of window system framebuffer. This
+	 * is a reference image to test MSAA with polygon smooth.
+	 */
+	glBindFramebuffer(GL_READ_FRAMEBUFFER, ms_fbo.handle);
+	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
+	glBlitFramebuffer(0, 0, pattern_width, pattern_height,
+			  pattern_width, 0, 2 * pattern_width, pattern_height,
+			  GL_COLOR_BUFFER_BIT, GL_NEAREST);
+
+	/* Now draw test pattern in mulisample ms_fbo with GL_POLYGON_SMOOTH
+	 * enabled
+	 */
+	glDisable(GL_DEPTH_TEST);
+	glEnable(GL_POLYGON_SMOOTH);
+	glHint(GL_POLYGON_SMOOTH_HINT, GL_NICEST);
+
+	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, ms_fbo.handle);
+	ms_fbo.set_viewport();
+
+	glClear(buffer_to_test);
+	test_pattern->draw(proj);
+
+	glDisable(GL_POLYGON_SMOOTH);
+
+	/* Blit ms_fbo to the left half of window system framebuffer. This
+	 * is the test image.
+	 */
+	glBindFramebuffer(GL_READ_FRAMEBUFFER, ms_fbo.handle);
+	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
+	glBlitFramebuffer(0, 0, pattern_width, pattern_height,
+			  0, 0, pattern_width, pattern_height,
+			  GL_COLOR_BUFFER_BIT, GL_NEAREST);
+
+	/* Check that the left and right halves of the screen match. If they
+	 * don't, then GL_POLYGON_SMOOTH is not ignored with multisample
+	 * rendering.
+	 */
+	glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
+	pass = piglit_probe_rect_halves_equal_rgba(0, 0, piglit_width,
+						   piglit_height) && pass;
+	pass = piglit_check_gl_error(GL_NO_ERROR) && pass;
+
+	piglit_present_results();
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}